1. Technical Field
This invention relates to a window covering and, more particularly, to a one-way viewing window covering for providing increased privacy.
2. Prior Art
Vertical louver type blind systems, similar to Venetian blinds in concept and operation, but formed of a large number of vertically extending elongated blind slats or louvers each pivoted about a vertical center axis for adjustment between open, closed, and desired intermediate positions, and slideable along upper and lower guide tracks have come into wide use as window blind systems, light transmission control or decorative control of transparent partitions or dividers in office space, and similar applications.
More recently, decorative vertical blind systems of similar construction, but wherein the vertically elongated blind slats are hung from an upper channel track, channel moldings, drapery rod or the like, with the blinds in some cases covered with decorator fabric, have come into use. These blind systems, when shut, impede not only the vision of those from the outside but also the occupants of the residency can not see what is going on outside their own residence.
Law enforcement officials often have a need to maintain continuous and surreptitious observation of buildings or other locations, sometimes over extended periods of time. It is often desirable that they should be able to maintain such surveillance from residencies, but it is usually difficult to do so for any length of time, since persons remaining in a residence with no window covering for extended time periods become highly obvious, and attract both notice and suspicion.
However, while such window coverings of one-way viewing material do permit observations by persons occupying a residence, they do so only imperfectly. Depending on the material used, some authorities estimate a reduction of visual quality and brilliance of as much as 50%.
Accordingly, a need remains for a one-way viewing window covering that overcomes the above-noted shortcomings.